added all APIs after testing them.

backend/controllers/expense.js

@@ -0,0 +1,80 @@
+const Expense = require('../models/expense');
+const User = require('../models/user')
+const { dateBeforeXFromNow } = require('../utilities/date');
+
+module.exports = {
+	addNewExpense: async (req, res) => {
+		const { body } = req;
+		try {
+			const user = await User.findById(body.userID);
+			const { userID, category, amount } = body;
+			if (!user.categories.includes(category)) {
+				return res.status(400).json({ message: "invalid category" });
+			}
+			if (amount > user.amountLeft) {
+				return res.status(400).json({ message: "budget not enough" });
+			}
+			const expense = new Expense({ userID, category, amount });
+			user.currentExpensesIDs.push(expense._id);
+			user.amountLeft = user.amountLeft - amount;
+			await expense.save();
+			await user.save();
+			res.status(200).json({ message: "expense saved", id: expense._id });
+		} catch (e) {
+			console.log(e);
+			res.status(400).json({ message: "expense not saved" });
+		}
+	},
+
+	// only update amount or deleted
+	updateExpense: async (req, res) => {
+		const { body } = req;
+		try {
+			const { userID, amount, deleted } = body;
+			const { id } = req.params;
+			const user = await User.findById(userID);
+			const expense = await Expense.findById(id);
+			if (deleted != undefined) {
+				if (expense.deleted !== deleted) {
+					let newAmount = user.amountLeft + ((2 * deleted - 1) * expense.amount);
+					if (newAmount >= 0) {
+						expense.deleted = deleted;
+						user.amountLeft = newAmount;
+						await expense.save();
+						await user.save();
+						return res.status(200).json({ message: "expense updated" });
+					}
+					return res.status(400).json({ message: "budget not enough" });
+				}
+			}
+			else if ((amount !== undefined) && (!expense.deleted)) {
+				let newAmount = user.amountLeft + (expense.amount - amount);
+				if (newAmount >= 0) {
+					expense.amount = amount;
+					user.amountLeft = newAmount;
+					await expense.save();
+					await user.save();
+					return res.status(200).json({ message: "expense updated" });
+				}
+				return res.status(400).json({ message: "budget not enough" });
+			}
+		} catch (e) {
+			console.log(e);
+			res.status(400).json({ message: "expense not updated" });
+		}
+	},
+
+	// gives expense data upto x days from now
+	getSummaryUptoXDays: async (req, res) => {
+		const { body } = req;
+		try {
+			const { userID } = body;
+			const { days } = req.query;
+			const expenses = await Expense.find({ userID }).where('date').gt(dateBeforeXFromNow(days)).sort('date');
+			res.status(200).json({ data: expenses, message: "data retrieved" });
+		} catch (e) {
+			console.log(e);
+			res.status(400).json({ message: "data could not be retrieved" });
+		}
+	}
+}

backend/controllers/user.js

@@ -1,6 +1,8 @@
-const User = require('../models/user')
+const User = require('../models/user');
+const Expense = require('../models/expense');
 const { hashPassword, verifyPassword } = require('../utilities/managePasswords')
 const { genJWT, verifyJWT } = require('../utilities/jwtAuth');
+const expense = require('../models/expense');
 
 module.exports = {
 	signUp: async (req, res) => {
@@ -11,31 +13,81 @@ module.exports = {
 			const newUser = new User({ username: username, password: secPassword });
 			await newUser.save();
 
-			const token = genJWT({userId: newUser.id});
-			res.status(200).json({token: token, message: "user details saved"});
+			const token = genJWT({ userID: newUser.id });
+			res.status(200).json({ token: token, message: "user details saved" });
 		} catch (e) {
 			console.log("error occured", e);
-			res.status(500).json({message: "server error occurred"})
+			res.status(400).json({ message: "user details not saved" });
 		}
 	},
 	login: async (req, res) => {
 		const { username, password } = req.body;
-		try{
-			const user = await User.findOne({username});
-			if(!user){
-				res.status(401).json({message: "please login with correct credentials"});
-			}else{
+		try {
+			const user = await User.findOne({ username });
+			if (!user) {
+				res.status(401).json({ message: "please login with correct credentials" });
+			} else {
 				const isCorrPass = await verifyPassword(password, user.password);
-				if(!isCorrPass){
-					res.status(401).json({message: "please login with correct credentials"});
-				}else{
-					const token = genJWT({userId: user.id});
-					res.status(200).json({token: token, message: "user logged in successfully"});
+				if (!isCorrPass) {
+					res.status(401).json({ message: "please login with correct credentials" });
+				} else {
+					const token = genJWT({ userID: user.id });
+					res.status(200).json({ token: token, message: "user logged in successfully" });
 				}
 			}
-		}catch(e){
+		} catch (e) {
 			console.log("error occured", e);
-			res.status(500).json({message: "server error occurred"})
+			res.status(500).json({ message: "server error occurred" })
+		}
+	},
+	updateSetting: async (req, res) => {
+		const { body } = req;
+		try {
+			const { budget, categories, userID} = body;
+			console.log({userID})
+			const user = await User.findById(userID);
+			user.budget = budget;
+			user.amountLeft = budget;
+			user.categories = categories;
+			await Expense.deleteMany({ "_id": { "$in": user.currentExpensesIDs } });
+			user.currentExpensesIDs = [];
+			await user.save();
+			res.status(200).json({ message: "setting updated" });
+		} catch (e) {
+			console.log(e);
+			res.status(400).json({ message: "setting not updated" });
+		}
+	},
+	currentExpenses: async (req, res) => {
+		const { body } = req;
+		try {
+			const user = await User.
+				findById(body.userID).
+				populate("currentExpensesIDs")
+			let data = [];
+			if (user.currentExpensesIDs.length > 0 && user.currentExpensesIDs[0].date.toDateString() != new Date().toDateString()) {
+				user.currentExpensesIDs = [];
+				user.amountLeft = user.budget;
+				user.save();
+			} else {
+				data = user.currentExpensesIDs.map(expense => {
+					return { "amount": expense.amount, "category": expense.category, "deleted": expense.deleted, "id": expense._id}
+				})
+			}
+			res.status(200).json({ data: data, message: "current expenses retrieved" });
+		} catch (e) {
+			console.log(e);
+			res.status(400).json({ message: "could not get current expenses" });
+		}
+	},
+	getDetails: async (req, res) => {
+		const { body } = req;
+		try {
+			const { userID } = body;
+			const user = await User.findById(userID).select("-_id username budget amountLeft categories");
+			return res.status(200).json({ data: user, message: "user details retrieved" });
+		} catch (e) {
+			res.status(400).json({ message: "could not retrieve user details" });
 		}
 	}
 }

backend/routes/expense.js

@@ -0,0 +1,9 @@
+const router = require('express').Router()
+const { addNewExpense, updateExpense, getSummaryUptoXDays } = require('../controllers/expense');
+const getUserFromJWT = require('../middlewares/validateUser');
+
+router.post('/new', getUserFromJWT, addNewExpense);
+router.put('/update/:id', getUserFromJWT, updateExpense);
+router.get("/summaryUpto", getUserFromJWT, getSummaryUptoXDays)
+
+module.exports = router;

backend/routes/user.js

@@ -1,8 +1,11 @@
 const router = require('express').Router()
-const { signUp, login } = require('../controllers/user')
-
+const { signUp, login, updateSetting, currentExpenses, getDetails} = require('../controllers/user')
+const getUserFromJWT = require('../middlewares/validateUser');
 
 router.post('/signUp', signUp);
 router.post('/login', login);
+router.put('/updateSetting', getUserFromJWT, updateSetting);
+router.get('/currentExpenses', getUserFromJWT, currentExpenses);
+router.get('/getDetails', getUserFromJWT, getDetails);
 
 module.exports = router;

backend/utilities/date.js

@@ -0,0 +1,9 @@
+
+
+const dateBeforeXFromNow = (daysBefore) => {
+	const date = new Date();
+	date.setDate(date.getDate() - daysBefore);
+	return date;
+}
+
+module.exports = { dateBeforeXFromNow };

backend/utilities/general.js

@@ -0,0 +1,6 @@
+const assert = function (condition, message) {
+	if (!condition)
+		throw Error('Assert failed: ' + (message || ''));
+};
+
+module.exports = { assert }